Fix XMSS keygen param fallback

F/3306

tools/keytools/keygen.c

@@ -987,7 +987,7 @@ static void keygen_xmss(const char *priv_fname, uint32_t id_mask)
         exit(1);
     }
 
-    if (xmss_params != NULL)
+    if (xmss_params == NULL)
         xmss_params = WOLFBOOT_XMSS_PARAMS;
 
     ret = wc_XmssKey_SetParamStr(&key, xmss_params);

tools/unit-tests/Makefile

@@ -55,7 +55,8 @@ TESTS:=unit-parser unit-fdt unit-extflash unit-string unit-spi-flash unit-aes128
        unit-update-disk unit-multiboot unit-boot-x86-fsp unit-loader-tpm-init unit-qspi-flash unit-fwtpm-stub unit-tpm-rsa-exp \
        unit-image-nopart unit-image-sha384 unit-image-sha3-384 unit-store-sbrk \
        unit-tpm-blob unit-policy-create unit-policy-sign unit-rot-auth unit-sdhci-response-bits \
-       unit-sdhci-disk-unaligned unit-sign-encrypted-output
+       unit-sdhci-disk-unaligned unit-sign-encrypted-output \
+       unit-keygen-xmss-params
 TESTS+=unit-tpm-check-rot-auth
 TESTS+=unit-tpm-api-names
 
@@ -215,6 +216,13 @@ unit-sign-encrypted-output: ../../include/target.h unit-sign-encrypted-output.c
 		-DWOLFBOOT_XMSS_PARAMS=\"XMSS-SHA2_10_256\" \
 		-ffunction-sections -fdata-sections \
 		$(LDFLAGS) -Wl,--gc-sections
+
+unit-keygen-xmss-params: ../../include/target.h unit-keygen-xmss-params.c
+	gcc -o $@ $^ -I../keytools $(CFLAGS) -DML_DSA_LEVEL=2 \
+		-D"LMS_LEVELS=1" -D"LMS_HEIGHT=10" -D"LMS_WINTERNITZ=8" \
+		-DWOLFBOOT_XMSS_PARAMS=\"XMSS-SHA2_10_256\" \
+		-ffunction-sections -fdata-sections \
+		$(LDFLAGS) -Wl,--gc-sections
 unit-rot-auth: ../../include/target.h unit-rot-auth.c \
 		$(WOLFBOOT_LIB_WOLFSSL)/wolfcrypt/src/memory.c
 	gcc -o $@ $^ -I../tpm $(CFLAGS) -I$(WOLFBOOT_LIB_WOLFTPM) -DWOLFBOOT_TPM \

tools/unit-tests/unit-keygen-xmss-params.c

@@ -0,0 +1,195 @@
+#include <check.h>
+#include <setjmp.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+static const char *mock_xmss_param;
+static int mock_exit_code;
+static jmp_buf mock_exit_env;
+
+static void mock_exit(int code);
+
+#define main wolfboot_keygen_main
+#define exit mock_exit
+#define wc_XmssKey_Init mock_wc_XmssKey_Init
+#define wc_XmssKey_SetParamStr mock_wc_XmssKey_SetParamStr
+#define wc_XmssKey_SetWriteCb mock_wc_XmssKey_SetWriteCb
+#define wc_XmssKey_SetReadCb mock_wc_XmssKey_SetReadCb
+#define wc_XmssKey_SetContext mock_wc_XmssKey_SetContext
+#define wc_XmssKey_MakeKey mock_wc_XmssKey_MakeKey
+#define wc_XmssKey_GetPrivLen mock_wc_XmssKey_GetPrivLen
+#define wc_XmssKey_ExportPubRaw mock_wc_XmssKey_ExportPubRaw
+#define wc_XmssKey_Free mock_wc_XmssKey_Free
+#define wc_ForceZero mock_wc_ForceZero
+#include "../keytools/keygen.c"
+#undef wc_ForceZero
+#undef wc_XmssKey_Free
+#undef wc_XmssKey_ExportPubRaw
+#undef wc_XmssKey_GetPrivLen
+#undef wc_XmssKey_MakeKey
+#undef wc_XmssKey_SetContext
+#undef wc_XmssKey_SetReadCb
+#undef wc_XmssKey_SetWriteCb
+#undef wc_XmssKey_SetParamStr
+#undef wc_XmssKey_Init
+#undef exit
+#undef main
+
+static void mock_exit(int code)
+{
+    mock_exit_code = code;
+    longjmp(mock_exit_env, 1);
+}
+
+int mock_wc_XmssKey_Init(XmssKey *key, void *heap, int devId)
+{
+    (void)key;
+    (void)heap;
+    (void)devId;
+
+    return 0;
+}
+
+int mock_wc_XmssKey_SetParamStr(XmssKey *key, const char *str)
+{
+    (void)key;
+    mock_xmss_param = str;
+    return 0;
+}
+
+int mock_wc_XmssKey_SetWriteCb(XmssKey *key, wc_xmss_write_private_key_cb write_cb)
+{
+    (void)key;
+    (void)write_cb;
+
+    return -1;
+}
+
+int mock_wc_XmssKey_SetReadCb(XmssKey *key, wc_xmss_read_private_key_cb read_cb)
+{
+    (void)key;
+    (void)read_cb;
+
+    return 0;
+}
+
+int mock_wc_XmssKey_SetContext(XmssKey *key, void *context)
+{
+    (void)key;
+    (void)context;
+
+    return 0;
+}
+
+int mock_wc_XmssKey_MakeKey(XmssKey *key, WC_RNG *rng)
+{
+    (void)key;
+    (void)rng;
+
+    return 0;
+}
+
+int mock_wc_XmssKey_GetPrivLen(const XmssKey *key, word32 *len)
+{
+    (void)key;
+    *len = 0;
+    return 0;
+}
+
+int mock_wc_XmssKey_ExportPubRaw(const XmssKey *key, byte *out, word32 *outLen)
+{
+    (void)key;
+    (void)out;
+    (void)outLen;
+
+    return 0;
+}
+
+void mock_wc_XmssKey_Free(XmssKey *key)
+{
+    (void)key;
+}
+
+void mock_wc_ForceZero(void *mem, size_t len)
+{
+    (void)mem;
+    (void)len;
+}
+
+static void setup(void)
+{
+    mock_xmss_param = NULL;
+    mock_exit_code = 0;
+    unsetenv("XMSS_PARAMS");
+}
+
+static void teardown(void)
+{
+    unsetenv("XMSS_PARAMS");
+}
+
+static void run_keygen_xmss(void)
+{
+    int jumped;
+
+    jumped = setjmp(mock_exit_env);
+    if (jumped == 0) {
+        keygen_xmss("ignored.xmss", 0);
+    }
+
+    ck_assert_int_eq(jumped, 1);
+    ck_assert_int_eq(mock_exit_code, 1);
+}
+
+START_TEST(test_keygen_xmss_uses_env_param_when_set)
+{
+    const char *expected = "XMSSMT-SHA2_20/2_256";
+
+    ck_assert_int_eq(setenv("XMSS_PARAMS", expected, 1), 0);
+
+    run_keygen_xmss();
+
+    ck_assert_ptr_nonnull(mock_xmss_param);
+    ck_assert_str_eq(mock_xmss_param, expected);
+}
+END_TEST
+
+START_TEST(test_keygen_xmss_uses_default_param_when_env_unset)
+{
+    run_keygen_xmss();
+
+    ck_assert_ptr_nonnull(mock_xmss_param);
+    ck_assert_str_eq(mock_xmss_param, WOLFBOOT_XMSS_PARAMS);
+}
+END_TEST
+
+static Suite *keygen_xmss_suite(void)
+{
+    Suite *s;
+    TCase *tc;
+
+    s = suite_create("keygen_xmss");
+    tc = tcase_create("xmss_params");
+    tcase_add_checked_fixture(tc, setup, teardown);
+    tcase_add_test(tc, test_keygen_xmss_uses_env_param_when_set);
+    tcase_add_test(tc, test_keygen_xmss_uses_default_param_when_env_unset);
+    suite_add_tcase(s, tc);
+
+    return s;
+}
+
+int main(void)
+{
+    Suite *s;
+    SRunner *sr;
+    int failed;
+
+    s = keygen_xmss_suite();
+    sr = srunner_create(s);
+    srunner_run_all(sr, CK_NORMAL);
+    failed = srunner_ntests_failed(sr);
+    srunner_free(sr);
+
+    return failed == 0 ? 0 : 1;
+}